Sol Messinger was just 7 when he stood with his father at the rail of the ocean liner St. Louis and stared into the gathering darkness. But nearly eight decades later, Messinger still recalls the lights of Miami glittering off the bow, so near to him and more than 900 fellow Jewish refugees aboard, yet beyond their reach.

Today, "I look out into the ocean and I get this queasy feeling," says Messinger, whose family escaped Europe for the U.S. three years after American officials turned away the vessel in 1939. Now 83, he is a pathologist in Buffalo, New York. "The Jews did not pose any threat to the U.S... It's really unforgivable."

Now, fresh angst about whether to admit refugees or turn them away has put the spotlight back on the shunning of the St. Louis and other decisions, now widely regretted, by U.S. officials before and during World War II.

A week after the Islamic State terrorist group killed 130 people in Paris, a backlash against the U.S. admitting Syrian refugees — most of them Muslims — has fueled a bitter debate, with politicians, pundits and others drawing lines between present and past.

There are differences between now and then. But disturbing similarities between the rhetoric of today and the attitudes of the U.S. public and officials during World War II make that history worth recalling, scholars say, as the country confronts new fears of terrorism.

"No historical parallel is perfect, obviously," says Allan Lichtman, co-author of "FDR and the Jews" and a professor of history at American University.

But U.S. limits on refugees during World War II, influenced by anti-Semitism, were fed by fears the Nazis "would plant agents, spies and saboteurs among the Jewish refugees and that they would pressure the Jews, particularly those whose families were still in Germany, to act as agents on behalf of the Third Reich," Lichtman said.

"Those arguments are chillingly similar to the arguments being made against the admission of the Syrian refugees."

Lichtman isn't alone in making the comparison.

On Monday, an Ohio professor, Peter Shulman of Case Western Reserve University, used Twitter to post results from a 1938 public opinion poll showing Americans overwhelmingly rejected admission of German Jews in the years leading up to the outbreak of war.

The reaction "was instantaneous and totally overwhelming. It was like nothing I've ever experienced before," said Shulman, who was been posting historical tidbits for about three years. One of his tweets of the decades-old polling data has been relayed 4,600 times, cited by commentators in The Washington Post, Time and other publications.

"When we sent Jews back to Germany and when we sent Japanese to internment camps, we regretted it and we will regret this as well," Rep. Luis Gutierrez, D-Illinois, said before 47 House Democrats and 242 Republicans voted this week for a bill to put new security limits on a plan by President Barack Obama to admit 10,000 Syrian refugees over the next year.

On Wednesday, New York Mayor Bill DeBlasio, criticizing a number of Republican governors for opposing admission of Syrian refugees, cited the 1938 poll — in which 67.4 percent of Americans said the U.S. should try to keep German and Austrian refugees out of the country and 61 percent opposed allowing 10,000 German Jewish children to enter.

"We are not going to make that mistake in our time, and voices of intolerance and voices of division are not going to cause us to do something that is against our values," DeBlasio said.

The comparison has been rejected by some critics.

"This is prima facie nonsense," Ian Tuttle wrote Wednesday in the conservative journal National Review. "The first and most obvious difference: There was no international conspiracy of German Jews in the 1930s attempting to carry out daily attacks on civilians on several continents."

But debate was stoked further when the Democratic mayor of Roanoke, Virginia, David Bowers, noted the U.S. detention of thousands of Japanese-Americans in camps in a call to bar Syrian refugees.

"It appears that the threat of harm to America from ISIS now is just as real and serious as that from our enemies then," Bowers said in a statement issued Wednesday.

Such rhetoric continues a long pattern in U.S. politics of labeling refugees as a threat, whether those fleeing the Nazis, refugees of the Hungarian Revolution or boat people uprooted by the Vietnam War, said Kelly Greenhill, author of "Weapons of Mass Migration: Forced Displacement, Coercion and Foreign Policy."

"Every time this country is confronted with ... a visible influx of people, the issue becomes politicized," said Greenhill, a professor of political science at Tufts University and a research fellow at Harvard University's school of government. "This is a movie we've seen before and it's sort of unfortunate, but it has a curious sameness across time, which doesn't make it better."

It's easily forgotten now, but the 1930s saw widespread disdain for European Jews, Lichtman said. Opposition to admitting refugees was heightened by the economic worries left by the Great Depression. Those public attitudes were reinforced by the U.S. State Department and other agencies, which worked to limit an influx of Jews that FBI Director J. Edgar Hoover labeled as potential infiltrators, he said.

When President Franklin Delano Roosevelt pondered relaxation of refugee quotas, Vice President John Nance Garner counseled that if Congress were allowed to vote in private, the legislators would ban immigration altogether, Lichtman said.

In the years since, the U.S. has become the world's largest recipient of international refugees.

But of the 784,000 refugees resettled in the U.S. since the September 11, 2001 attacks, just three have been arrested for planning terrorist activities, according to the Migration Policy Institute, a non-partisan think tank. Only one of those, an Uzbeki immigrant, spoke of targeting the U.S. itself, but had no specific plans, the institute said.

While taking in 10,000 Syrian refugees would be a significant increase from the roughly 2,000 admitted since the country's civil war began in 2011, it is a fraction of those going to other countries. Up to 800,000 people are expected to seek asylum in Germany by the end of this year, according to MPI.

Messinger, whose family found brief refuge in Belgium after both Cuban and American officials turned away the St. Louis, sees some similarities between that experience and the one endured by those fleeing Syria. But it's not the same, he says.

Jews fled Europe because of discrimination and mistreatment based on their religion, he said, recalling that just six weeks after his family won entry to the U.S. in 1942 all the remaining Jews in their village were shipped off to a concentration camp.

But the danger Syrians face is less because of their religion than the geopolitics that has put their homes in a war zone. What's more, unlike fears that today's refugees may harbor terrorists, nobody aboard the St. Louis posed a potential threat.

"I understand that Syrians who come here are vetted very carefully and so the chances of some terrorist getting through are probably small, but they are not non-existent," he said.

But Robert Krakow, whose SS St. Louis Legacy Project has documented the history of the voyage and successfully pushed for an apology from the U.S. State Department, said he sees more similarities than differences between the refugees of different eras.

In 1939, American officials turned away the ship of Jewish refugees because it was politically expedient, said Krakow, who lives in Boca Raton, Florida.

Although the calculus may be a little different with today's Syrian refugees, "the parallel for me is politics," Krakow says.

"Ultimately, it's all grounded in the human condition. It's grounded in human need and suffering, and here's a case where we can do something. ... It's a practical question and there's a solution to it and I find it disturbing the way this hysteria is invoked for political gain."